Bicycle Therapeutics and Cancer Research UK have initiated the first clinical study to assess a bicyclic peptide, evaluating its potential in patients with advanced solid tumours.

The first patient has now been dosed in a Phase I/IIa trial with BT1718, a first-in-class Bicycle Toxin Conjugate that targets Membrane Type 1 Matrix Metalloproteinase (MT1-MMP/MMP-14), which is highly expressed in solid tumours.

The trial aims to enroll around 120-patients, and will consist of a rapid dose escalation phase followed by evaluation of two schedules of BT1718.

BT1718 is the first example of the firm’s drug conjugate technology, in which toxic chemical payloads are targeted specifically to malignant tumours, minimising systemic toxin exposure through renal clearance.

According to the partners, BT1718 has demonstrated “promising target-dependent efficacy in preclinical models, including both cell- and patient-derived xenografts that are resistant to treatment with standards of care.”

Also, on the safety side, the therapy has shown only a subset of the toxicities typically associated with other highly potent cancer treatments, they noted.

“The initiation of this study is a landmark event for the company and for our technology,” said Maria Koehler, Bicycle’s chief medical officer.

“We believe that Bicycles, because of their small size and exquisite selectivity, could provide meaningful efficacy to patients suffering from cancer and avoid the toxicities associated with other classes of highly potent anti-cancer drugs. We are delighted to be exploring its potential in collaboration with Cancer Research UK.”

CR UK’s Centre for Drug Development (CDD) is sponsoring and co-managing the trial.

Under the terms of the deal, Bicycle retains the right to further advance the BT1718 programme, at which point an undisclosed payment split between cash and equity, success based milestones and royalty payments would be made to the charity.